The old adage among carpenters, woodworkers and machinists in order to avoid costly and time-consuming mistakes is “measure twice and cut once”. This guideline is normally learned only through the experiences of making many mistakes in the workshop.
Woodworkers and machinists are constantly seeking more accurate and reliable techniques for sawing, routing, milling, turning, and drilling wood and metal. One variable that has consistently evaded precision is the requirements for accurately gauging the amount of material to be removed during a processing step.